It's not just films that have a cheeky scene after the credits, but games as well. It's understandable that developers wants to show us everyone that worked on the game, but do they expect anyone to actually read through the credits? Making it un-skippable is just downright annoying to be honest and with games like AC3 you have to sit through the credits just to be able to carry on playing. In fact, in the time taken for the full AC3 credits I managed to not only cook myself a delicious lunch but complete my tax return form as well as clean the sink, hoover the flat, pop down the local for a few pints and do the washing. Do developers like Ubisoft really expect people to sit through all of that? Of course not, make it skippable. If someone wants to know who did what, I'm sure they can Google it.